Internet Protocol (IP) is the most widely used technology at layer 3 of the Open System Interconnection (OSI) model for the Internet. At layer 4 of the OSI model, Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) are the most widely used protocols for IP network. The design of the Internet protocols is based on the end-to-end principle. The network infrastructure is considered inherently unreliable at any single network element or transmission medium and is dynamic in terms of availability of links and nodes. No central monitoring or performance measurement facility exists that tracks or maintains the state of the network. For the benefit of reducing network complexity, the intelligence in the network is purposely located in the end nodes. As a consequence of this design, the Internet Protocol only provides best-effort delivery and its service is characterized as unreliable without Quality of Service (QoS). Furthermore, TCP and UDP also have no QoS by default. Therefore, the data transmission in an IP network based on TCP or UDP has no QoS.